Replies

1. 
   Ronbaby | Apr 26, 2003 01:37am | #1

   Those questions cant be answered here. Who knows what the loads above them are. You need to consult an architect or engineer.

2. 
   RichBeckman | Apr 26, 2003 02:12am | #2

   I think Ronald is correct, especially concerning question #2.

   I'm curious, what flooring system is going to span the 32" (I suppose it is actually only a 26" or 27" span?)?

   Rich Beckman

   Another day, another tool.

1. 
   poppa | Apr 26, 2003 02:27am | #3

   1 1/8 inch T&G plywood will span 48 inch.  Concerned if 6x6's used as floor joist will span 12 feet at 32 inches o.c.

   Bob

1. 
   FrankB89 | Apr 26, 2003 02:45am | #4

   1 1/8" board WILL span 4', but where I've seen that done, the results were disappointing from a "firm" floor standpoint. 

   In my own home and a couple others, elephant board on 24" centered joists was good and provides a good base for some of the heavier floor finishes like tile.

   As to the span question:

   CABO Code allows a maximum span of 7'-3" w/2 X 6 on 32" centers and that's assuming you're using joist material with a modulus of elasticity od 1.3 (which is usually a good grade of Doug fir or Larch and assuming 40psi live load and 10psi dead load).

   To the Code, the best span you're going to get with 2 X 6 is 10'-0" and that is on 12" centers!

   I suggest you trot down to your local library and get a code book (or buy one for about $75), or consult with a designer or engineer. 

2. 
   jonblakemore | Apr 26, 2003 02:45am | #5

   Just out of curiousity, what is the project you're building?

   I agree with the original answers to your question.  You need a professional to look at this. 

   Jon Blakemore

1. 
   poppa | Apr 26, 2003 02:53am | #6

   Log cabin

3. 
   Piffin | Apr 26, 2003 03:46am | #7

   A 6x6 just isn't deep enough for that span. I've seen historical buildings done with that detail or simnilar using strong antigue hemlock or oak and every one of them had bounce and sag. 6x8 would probably barely have what it takes, depending on the variables - type of wood, room use, eetc.

   The second question is wide open with variables about soil conditions, total load, etc.

   That is why yoiu are being advised to seek out an engineer. You are proposing something unigue and not covered in standard tables.

   .

   Excellence is its own reward!

4. 
   fdampier5 | Apr 26, 2003 05:14am | #8

   I'll take a shot at it..  I used 6x6 white oak (species makes a differance)   with 24 inch on center to span 8 feet.  for decking I used two inch thick  eastern white pine as sub floor with 1 inch thick hard maple as finish floor. 

      Jumping with all my wieght doesn't wiggle a thing.

     to the techincal minded. the formula for figuring this out is listed in the UBC, (uniform building code)  which most libraries will have.  Or you can check out Jack Soborns book and it has the formulas in the back. (as does Ted Bensons  first book, building the timberframe house).   There is also a book available to build post and beam buildings for farm use  (sorry I forget the tittle)..

     As for the concrete columns I saw the answer to that in the UBC but can't remember the chapter..

     So either go to your library or hire an engineer..